/*
 * @Author: chen haoxuan
 * @Date: 2021-06-24 21:38:59
 * @LastEditTime: 2021-06-24 21:39:24
 */
#include<iostream>
using namespace std;
int main()
{
    int n, i, j, k;
    cout<<"Please enter the number of lines: ";
    cin>>n;
    for (i = 0;  i < n; i++)
    {
        for (j = 0; j < 20 - i; j++)
        cout<<" ";
        for (k = 0; k < 2 * (i + 1) - 1; k++)
        cout<<"B";
        cout<<endl;
    }
    return 0;
}
